1. Field of the Invention
The present invention relates to a light source unit, a light source apparatus utilizing the light source unit, and a projector utilizing the light source apparatus.
2. Description of the Related Art
Currently, high-luminance ultra-high pressure mercury lamps and metal halide lamps are used much as light sources of data projectors. However, since they have a large heating value, these light emitting elements have had a drawback that a cooling mechanism becomes complicated in construction and large in size. Because of this, small projector light sources have been proposed which utilize light emitting diodes or the like whose heating value is relatively small. For example, the Japanese Unexamined Patent Publication No. 2004-220015 proposes a projector which utilizes a light source in which light emitting elements such as light emitting diodes or the like are arranged in an array or arrays.
Light sources unit of this type are used much in which light emitting diodes are used as light emitting elements which are arranged into arrays, the light emitting elements are mounted on a substrate, the light source unit is covered with a dome-shaped sealing portion, and light that is emitted from the light emitting elements and which is allowed to pass through the sealing portion is made into a bundle of parallel rays of light by a collimator lens which is formed externally into the shape of paraboloid of revolution or ellipsoid of revolution so as to be emitted to the outside.
With the light source unit that has been described above, however, since the collimator lens which is formed externally into the shape of paraboloid of revolution, the external shape of the collimator lens becomes large, resulting in a problem that a plurality of light emitting elements cannot be arranged highly densely.
The prevent invention was made in view of the problem inherent in the related art, and an object thereof is to provide a light source unit which can be arranged highly densely, a light source apparatus which utilizes the light source unit, and a projector which utilizes the light source apparatus.